Traditionally flexible pipe is utilised to transport production fluids, such as oil and/or gas and/or water, from one location to another. Flexible pipe is particularly useful in connecting a sub-sea location to a sea level location. Flexible pipe is generally formed as an assembly of a portion of flexible pipe body and one or more end fittings. The pipe body is typically formed as a composite of layered materials that form a pressure-containing conduit. The pipe structure allows large deflections without causing bending stresses that impair the pipe's functionality over its lifetime. The pipe body is generally built up as a composite structure including metallic and polymer layers.
The end fittings of a flexible pipe may be used for connecting segments of flexible pipe together or for connecting them to terminal equipment such as a rigid sub-sea structures or floating facilities. As such amongst other varied uses, flexible pipe can be used to provide a riser assembly for transporting fluids from a sub-sea flow line to a floating structure. In such a riser assembly a first segment of flexible pipe may be connected to one or more further segments of flexible pipe. Each segment of flexible pipe includes at least one end fitting.
It is well-known that there are many varied problems associated with the provision of end fittings for ends of flexible pipe body. The end fittings must ensure both good fastening and good sealing. Particular problems occur when the various specific layers of the multi layer flexible pipe body are terminated. The flexible pipe body may include layers having very different material characteristics such as single polymer layers and/or interlocked metallic layers. The termination of each of these layers in an end fitting brings with it characteristic problems. For example, flexible pipe body typically includes a barrier layer formed generally as a polymer sheath or pressure sheath. Such a layer operates as a primary liquid retaining layer. To prevent rupture of such a layer or indeed any underlying layer under high pressure caused by the pressure of the transported fluid, an interlocked wire layer is often located outside the barrier layer. Armour layers formed by layers of wire may also be provided to sustain tensile loads and internal pressure. If a pressure armour layer is not supported along its length, it is possible for portions of the barrier layer or other such underlying layer to burst through under pressure and cause failure of the terminating structure.